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Subject: [Bug c++/103939] memset with sizeof in wrong place not detected ?
Date: Fri, 07 Jan 2022 13:43:50 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D103939

Eric Gallager <egallager at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |egallager at gcc dot gnu.o=
rg

--- Comment #2 from Eric Gallager <egallager at gcc dot gnu.org> ---
(In reply to Jonathan Wakely from comment #1)
> The docs explain why GCC's -Wmemset-transposed-args doesn't warn:
>=20
>   Warn for suspicious calls to the "memset" built-in function where the
> second
>   argument is not zero and the third argument is zero.  For example, the =
call
>   "memset (buf, sizeof buf, 0)" is diagnosed because "memset (buf, 0, siz=
eof
>   buf)" was meant instead.  The diagnostic is only emitted if the third
> argument
>   is a literal zero.
>=20
> So not warning for your case is by design.
>=20
> But it probably makes sense to warn if the second argument is a sizeof
> expression, whatever the value of the third argument.

What if both the second and third arguments are 'sizeof' expressions?=